COMMISSION 27 OF THE I. A. U.
          INFORMATION BULLETIN ON VARIABLE STARS
                      Number 3157

                                    Konkoly Observatory
                                    Budapest
                                    17  March 1988

                                    HU ISSN 0374 - 0676





                  THE VARIABILITY OF 53 Psc


   The B2.5IV star 53 Psc was suspected by Williams (1954) to be variable
with a period of about 0.09 days. Sareyan et al. (1979) found the star to be
slightly variable on two nights with about the same period found by Williams.
From radial velocity measurements on one night they obtain a significantly
shorter period of about 0.055 days. They concluded that the star is probably
a Beta Cep variable. Recently, Wolf (1987) obtained photometry of this star
during one night and found a large amplitude variation (0.035 magnitudes)
with a period of about 0.096 days. More recently, Le Contel et al. (1988)
could find no variation larger than 0.01 mag. from two nights in 1982
and 6 nights in 1987. This behaviour is most puzzling and the star
deserves closer attention.

   We report here results of intensive photometric monitoring of 53 Psc
during a continuous run from 3 Sep to 30 Sep 1986. As comparison stars we
used HR 26 and HR 254 which are the same two stars used by the previous
observers. We obtained a total of 147 observations of 53 Psc over 17 nights
through the Stromgren b filter using the 0.5-m reflector of the South African
Astronomical Observatory.
   Our results showed that 53 Psc and the two comparison stars were constant
to better than 4 millimags during this time. We performed a periodogram
analysis on 53 Psc and concluded that no significant periodic variations
existed with an amplitude larger than 2 millinags. We can thus be certain
that 53 Psc was constant to within this limit.
   Whereas the observations of Williams (1954) could be dismissed owing to
the reported poor observing conditions and those of Sareyan et al. (1979)
could be regarded as marginal, we cannot overlook the well-defined large
amplitude light curve found by Wolf (1987). Further observations of 53 Psc
could prove important to our understanding of variability among early-type
stars if such observations took place while the star was active. It is
possible that this star is subject to episodes of transient variability as
suspected for 22 Ori (Balona & Engelbrecht 1985).




                     L.A. BALONA and F. MARANG
                     South African Astronomical Observatory,
                     P.O. Box 9, Observatory 7935,
                     Cape,
                     South Africa.




References:



Balona, L.A. & Engelbrecht, C.A., 1985. Mon. Not. R. Astr. Soc., 214, 559. [BIBCODE 1985MNRAS.214..559B ]
Le Contel, J.M., Chapellier, E., Valtier, J.C., Rodriguez, E., Sedano, P.,
   Morel, P.J. & Le Contel, D., 1988. IBVS No. 3131.
Sareyan, J.P., Le Contel, J.M., Ducatel, D., & Valtier, J.C., 1979. Astron.
   Astrophys., 72, 313. [BIBCODE 1979A&A....72..313S ]
Williams, A.D., 1954. Publ. Astron. Soc. Pacific, 66, 88. [BIBCODE 1954PASP...66...88W ]
Wolf, M., 1987. IBVS No. 3003.